Appendicitis is a condition characterized by inflammation of the appendix. Cases typically require removal of the inflamed appendix, either by laparotomy or laparoscopy. Untreated, mortality is high, mainly because of peritonitis and shock.
Appendicitis is among many human diseases for which the diagnosis is complicated by the heterogeneity of its clinical presentation. Patients with many other disorders can present with symptoms similar to those of appendicitis. Examples include the following: pelvic inflammatory disease (PID) or tubo-ovarian abscess, endometriosis, ovarian cyst or torsion, ureterolithiasis and renal colic, degenerating uterine leiomyomata, diverticulitis, inflammatory bowel disease, colonic carcinoma, rectus sheath hematoma, cholecystitis, bacterial enteritis, viral gastroenteritis, mesenteric adenitis and omental torsion. It remains the most common surgical emergency of children, with initial diagnosis accuracy additionally challenged because of non-specific but similar symptoms of many other conditions. Delays in accurate diagnosis lead to increased mortality, morbidity and costs associated with the complications of appendicitis.
The use of high resolution computed tomography (CT) to identify appendiceal inflammation was hoped to improve both the diagnosis and treatment of appendicitis. Though variable, these improvements have been modest at best, with rates of unnecessary appendectomies and ruptures of 3-30% and 30-45%, respectively. In addition, availability of, and experience with, CT limit the usefulness of this approach. Furthermore, recently its use has been re-evaluated due to concerns of cancer risk due to radiation exposure. Ultrasonography is another imaging modality used to diagnose appendicitis, but ultrasonography requires a skilled operator, who may not be immediately available at night or on weekends, and the diagnostic accuracy of ultrasonography is limited.
Development of non-invasive diagnostics is therefore needed and desirable.